Molecular iodine adsorption within Hofmann-type structures M(L)[M′(CN)₄] (M = Ni, Co; M′ = Ni, Pd, Pt): impact of their composition

Abstract

A series of thermally stable Hofmann-type clathrate structures with the general formula M(pz)[M'(CN)4], where M and M' are bivalent metal ions M(II) = Ni(II), Co(II), M(II)' = Ni(II), Pd(II), Pt(II), and pz is the pyrazine bidentate ligand, was synthesized and investigated for the efficient entrapment of iodine (I2) in solution and in the gas phase. Iodine-containing clathrates thus prepared were analysed to determine the saturation capacity, thermal stability, guest-induced structural changes of the clathrate's lattice and the nature of the confined iodine according to the chemical composition of the host structure. An efficient confinement of about 1 I2 per unit cell is observed for the series of clathrates with the Ni(II) and Pd(II) ions in the square planar position whatever the bivalent metal ion in the octahedral position. Specific responses in the lattice adjustment are detected for Co(II) in the octahedral and Pd(II) in the square planar positions.

Supramolecular Organization in Confined Nanospaces

“…The environmental relevance of toxic gas capture [46] and the electric conductivity enhancement caused by iodine uptake [567,568] have raised great interest on the incorporation of dihalogen molecules in diverse hosts like clathrasils, [324,569] zeosils, [46,[569][570][571] and ALPOs, [572][573][574][575] but also organic salts, [576] organic zeolites, [567] Hofmann clathrates, [577,578] and other MOFs. [579][580][581] The structure and composition of the host determine the intermolecular interactions responsible of the capture/release mechanisms.…”

“…The environmental relevance of toxic gas capture and the electric conductivity enhancement caused by iodine uptake, have raised great interest on the incorporation of dihalogen molecules in diverse hosts like clathrasils,, zeosils,, and ALPOs, but also organic salts, organic zeolites, Hofmann clathrates,, and other MOFs …”

In Situ Growth of Ultrafine Pt Nanoparticles onto Hierarchical Co3O4 Nanosheet‐Assembled Microflowers for Efficient Electrocatalytic Hydrogen Evolution

“…The crystallographic structure of the formed product is examined by X‐ray diffraction (XRD). As can be observed from the XRD pattern (Figure 1 a), all of the strong diffraction peaks can be well indexed to the Hofmann‐typed coordination polymer (CP) of Co(pyrazine){Pt(CN) 4 }⋅ x H 2 O [15] without additional peaks from discernible impurities. As known, the bimetallic Hofmann‐typed CP, M(L) n [M′(CN) 4 ] (M=transition metal ions, L=monodentate/bidentate ligand, and M′=Ni, Pd or Pt) is generically composed of 2D extended metal cyanide sheets constituted by square‐planar [M′(CN) 4 ] 2 − centers equatorially linked to octahedral M II sites.…”

“…x H 2 O [15] withouta dditional peaks from discernible impurities. centers equatorially linked to octahedral M II sites.…”

An Efficient Method for Selective Desalination of Radioactive Iodine Anions by Using Gold Nanoparticles-Embedded Membrane Filter

“…Moreover, released radioactive iodines can cause severe contamination of soil, seawater and ground water owing to their high solubility in water. Therefore, a lot of remediation processes using various inorganic and organic adsorbents have been investigated to capture radioactive iodines in aqueous wastes 7,8,9,10,11,12,13,14,15,16,17,18,19,20 . Although extensive efforts have been devoted for the development of advanced adsorbent systems, the establishment of a decontamination method showing satisfactory performances under continuous in-flow condition was very limited.…”